Cereal grain sorting system and roll sorting machine

ABSTRACT

A cereal grain sorting system includes a wind force sorting device, a rough sorting device and a roll sorting device. The wind force sorting device is operative for selectively sorting light weight foreign materials from feedstock cereal grains. The rough sorting device is operative for selectively removing foreign materials having different diameters from the standard one from the feedstock cereal grains. The roll sorting device is operative for selectively removing foreign materials having different forms from the standard ones from the feedstock cereal grains having been subjected to the wind force sorting step as well as to the rough sorting step.

TECHNICAL FIELD

The present invention relates to a cereal grain sorting system capableof selectively and completely removing foreign materials such as coats,stem pieces, various seeds like mustard seeds and grass seeds, corn,dust, waste, stones, and metal pieces, or defective products such asworm-eaten beans, broken beans, and cracked beans from cereal grainssuch as soybeans or red beans, and to a roll sorting machine which canbe incorporated in the cereal grain sorting system.

BACKGROUND ART

Conventionally there has been used a sorting system comprising a roughsorting machine, a specific gravity sorting machine, and a spiralsorting machine for selectively removing foreign materials such ascoats, stem pieces, various seeds like mustard seeds and grass seeds,corn, dust, waste, stones, and metal pieces, or defective products suchas worm-eaten beans, broken beans, and cracked beans from cereal grainssuch as soybeans or red beans.

In this sorting system, foreign materials having different graindiameters from a specified one are selectively removed by the roughsorting machine, those having different specific gravities from astandard one are selectively removed by the specific gravity sortingmachine, and also those having different mass from a standard one areselectively removed with the spiral sorting machine by making use of thecentrifugal speed, and thus foreign materials and defective products areremoved from the feedstock cereal grains.

However, when the specific gravity sorting machine requiring a largevolume of air is operated for a long time in a sorting plant where 5 to20 tons of cereal grains not having been sorted yet in the very dustyatmosphere, clogging occurs in a cover for protecting the machine, orcracked beans drop to a section under the screen and are clogged betweenstatic airflow adjusting plates so that the sorting state alwayschanges, and when the airflow becomes smaller, light weight foreignmaterials are mixed in acceptable products, which remarkably lowers thesorting precision, and therefore it is required for the operator toalways monitor and adjust the machine or to clean the machine, and thework load is very heavy. In addition, the specific gravity sortingmachine requires a large volume of air to be supplied, which not onlymakes a cloud of dust and worsens the working environment, but alsocauses heavy noises of 100 phons or more.

In the spiral sorting machine, cereal grains are dropped along acircular inclined surface and foreign materials having different massfrom the cereal grains are selectively removed by making use of thecentrifugal speed, but adjustment for a size and a shape (flatness) ofthe feedstock cereal grains is not possible at all, so that the sortingprecision is rather low, and in addition, foreign materials such ascorns, broken beans, and stone pieces are collided by acceptableproducts continuously flowing along the inclined surfaces and are pushedout to the acceptable product side to be mixed therein, and when thecentrifugal speed drops due to the effect of dust or others in theatmosphere at the working site, the acceptable products may be mixed inforeign materials, which may in turn lowers the yield.

Further in the sorting system as described above, dust raised by thespecific gravity sorting machine are deposited around acceptableproducts, so that the acceptable products become dusty, and in addition,as the spiral sorting machine is a internally sealed type of device,dust is easily deposited inside the machine, and the dust released fromthe specific gravity sorting machine may cause operation fault or othertroubles of the spiral sorting machine, and therefore the operationalstability in long time use is rather low.

As a roll sorting machine which can be incorporated in a cereal grainsorting system, there has been known one in which an endless belt ishung over a lower roll and an upper roll positioned in parallel to anddiagonally above the lower roll and the upper roll is rotated so that atop surface of the belt moves to the upper roll. Also, there has beenknown another one in which the endless belt is oriented in the travelingdirection or in a direction perpendicular to the traveling direction(Japanese Patent Publication No. SHO 31-1361).

The present applicant has conducted hard and strenuous research anddevelopment efforts in the field of roll sorting machine, and developedseveral novel sorting machines including one capable of completelyseparating not only foreign materials which have flat, angular, orirregular spherical forms and can not rotate, but also defectiveproducts such as cracked beans and worm-eaten beans which have similarspherical forms as regular spherical forms and can rotate from sphericalbodies such as soybeans, red beans, and pearls each having a sphericalform, in which the distance required for sorting may be short and can bebuilt in a compact form because the twisted curved surface of theendless belt is utilized and also which can smoothly sort a largequantity of soybeans or the like (Japanese Patent Publication No. SHO57-28307). Another one capable of accurately sorting not only foreignmaterials having flat or angular forms, but also those like crackedbeans or worm-eaten beans which can rotate, enabling free and smoothadjustment for discharge percentages of sorted materials to an outletfor acceptable products and a second outlet for rejected products orforeign materials according to an open/close degree of a separationmeans, which can efficiently be formed into a multi-stage device with ashort sorting distance and can be built in compact form, and also whichcan efficiently screen a large volume of feedstock soybeans because itcan easily treat the feedstock soybeans piled up when fed with asaw-toothed plate (Japanese Patent Laid-Open Publication No. HEI10-165895).

However, in the conventional type of roll sorting machine, 1) as asupply rate of cereal grains from the feedstock cereal grains is notstable, sometimes cereal grains as overflow from the inlet of thefeedstock cereal grains may clog, and when a quantity of cereal grainssurpassing the processing capacity of the machine is supplied eventemporally, the sorting precision may become remarkably lower. 2) Cerealgrains such as soybeans have an oval form, and in the case of cerealgrains having an oval form, when a moving speed of a belt reaches aprespecified speed, each piece of the cereal grains rises up and startsrotating, which makes roll sorting possible, but a belt speed optimumfor starting rotation varies according to forms of the cereal grains,and therefore the sorting precision varies according to types of thecereal grains. 3) In case of a multiple stage roll sorting machine inwhich a plurality of roll sorting machines are piled up in the multiplestages, sprocket wheels of upper rolls of respective stages are linkedto each other with a chain, and the belts in the multiple stages aremoved simultaneously with one driving force source. Because of thisconfiguration, when a number of stages is large, the chain becomeslonger and troubles easily occur. Further, when oil is supplied formaintenance of the chain, sometimes the oil may spatter to contaminatethe feedstock cereal grains, and if the chain is left uncovered afterthe maintenance, it is very dangerous, which is disadvantageous for thesafety of operators.

DISCLOSURE OF THE INVENTION

The present invention was made to solve the problems described above,and it is an object of the present invention to provide a cereal grainsorting system which allows stable operations for a long time withoutrequiring supply of a large quantity of air, and which can provide highquality final products relatively quietly and keeping the sortingprecision and high production yield without further worsening theworking conditions.

The present invention was made also to solve the problems of the rollsorting machine described above, and it is an object of the presentinvention to provide a roll sorting machine which can insure safety forworkers and also can prevent the sorting precision from varying due todifferences of forms of cereal grains without causing the fed feedstockcereal grains to overflow from or clog the inlet of the sorting machine,without lowering the sorting machine caused by supply of a largequantity of cereal grains surpassing a regular throughput of the sortingmachine, and further without causing contamination of the cereal grains.

DISCLOSURE OF THE INVENTION

To solve the problems in the cereal grain sorting system as describedabove, the cereal grain sorting system according to the presentinvention comprises a wind force sorting process of selectively removinglight weight foreign materials from feedstock cereal grains, a roughsorting process of selectively removing foreign materials havingdifferent diameters from the feedstock cereal grains, and a roll sortingprocess of selectively removing foreign materials having different formsfrom the feedstock cereal grains having been subjected to the wind forcesorting process and the rough sorting process.

In the cereal grain sorting system according to the present invention,when magnetic foreign materials such as metal pieces are mixed in thefeedstock cereal grains, the magnetic foreign materials can selectivelyand efficiently be removed by providing a magnetic force sortingprocess, and this configuration is a preferable mode.

Further in the cereal grains sorting system according to the presentinvention, when stone pieces are mixed in the feedstock cereal grains,the stone pieces can efficiently be removed by further providing astone-piece removal process of selectively removing the stone piecesfrom the feedstock cereal grains, which is preferable.

In the cereal grain sorting system according to the present invention,when fine materials such as dust and mud are deposited on the feedstockcereal grains, by further providing a polishing process of removing thefine deposited materials from the feedstock cereal grains by polishing,the fine deposited materials such as dust and mud can efficiently beremoved, which is more preferable.

In the cereal grain sorting system according to the present invention,when it is necessary to sort the final products according to graindiameters, by further providing a grain diameter sorting process ofsorting the feedstock cereal grains according to the grain diameters, itis possible to sort the final products according to the gain diameters,which makes it possible to advantageously supply the final productssorted according to the grain diameters to satisfy the consumers'demands.

To solve the problems in the roll sorting machine described above, inthe roll sorting machine according to the present invention, an endlessbelt is hung over a lower belt and an upper roll positioned diagonallyabove the lower roll, the lower roll and upper roll are inclined in thesame direction at prespecified angles respectively with the inclinationangle of the lower roll smaller than that of the upper roll. Further oneor more saw-toothed plates are provided on a top surface of the endlessbelt, and, at the same time, a lengthy inclined discharge plateinclining downward in the sideward direction is provided at a side edgein the downwardly inclining side of the endless belt. This roll sortingmachine according to the present invention is characterized in that aconstant rate supply unit for supplying feedstock cereal grains at aspecified constant rate to a feedstock cereal grain inlet is provided sothat feedstock cereal grain supply rate can freely be adjusted.

Further, in the roll sorting machine according to the present invention,an endless belt is hung over a lower roll and an upper roll positioneddiagonally above the lower roll, the lower roll and upper roll areinclined in the same direction at prespecified angles respectively withthe inclination angle of the lower roll smaller than that of the upperroll. Further, one or more saw-toothed plates are provided on a topsurface of the endless belt, and, at the same time, a lengthy inclineddischarge plate inclining downward in the sideward direction is providedat a side edge in the downwardly inclining side of the endless belt.This sorting machine is characterized in that a speed-variable drivingforce source for changing a driving speed of the endless belt isprovided and the driving speed for the endless belt can freely bechanged or adjusted according to forms of fed feedstock cereal grains sothat the feedstock cereal grains rotate and drop.

Still further, in the roll sorting machine according to the presentinvention, an endless belt is hung over a lower roll and an upper rollpositioned diagonally above the lower roll, the lower roll and upperroll are inclined in the same direction at prespecified anglesrespectively with the inclination angle of the lower roll smaller thanthat of the upper roll. Further, one or more saw-toothed plates areprovided on a top surface of the endless belt, and, at the same time, alengthy inclined discharge plate inclining downward in the sidewarddirection is provided at a side edge in the downwardly inclining side ofthe endless belt. This roll sorting machine is characterized in that aconstant rate supply unit for supplying feedstock cereal grains at aprespecified rate to a feedstock cereal grain inlet, and a supply rateof the feedstock cereal grains can freely be adjusted. Further, aspeed-variable driving force source for changing a driving speed for theendless belt is provided and the driving speed for the endless belt canfreely be changed or adjusted according to forms of fed feedstock cerealgrains so that the feedstock cereal grains rotate and drop.

In the roll sorting machine, when the constant rate supply unit is avibration type of constant rate supply unit for supplying the feedstockcereal grains at a specified constant rate with vibration, a more stableand a more uniformed constant supply of feedstock cereal grains canadvantageously be performed.

In the roll sorting machine, when the speed-variable driving forcesource is a direct linkage type of speed-variable driving force sourcedirectly connected to an edge of this upper roll, use of a chain is notrequired, so that the problems such as chain troubles, contamination ofthe feedstock cereal grains, and those concerning the safety foroperators are advantageously eliminated.

In the roll sorting machine, by monitoring the cereal grains fed onto anupper surface of the endless belt by a monitor camera as to whether thecereal grains are rotating in the acceptable state and adjusting adriving speed for the endless belt so that the cereal grains rotate anddrop, it is to perform optimum roll sorting suited for forms of varioustypes of cereal grains. Further, it is possible to maintain the sortingprecision even if various types of cereal grains are fed, which is morepreferable.

Further in the roll sorting machine, by monitoring the cereal grains fedonto an upper surface of the endless belt by a monitor camera as towhether the cereal grains are rotating in the acceptable state andadjusting inclination angles of the upper roll and lower roll as well asan angle between a central axis of the upper roll and that of the lowerroll respectively, it is possible to insure optimal conditions for rollsorting, which is advantageous.

Further, when the roll sorting machine is embodied as a multiple stageroll sorting machine formed by stacking the roll sorting machines inmultiple stages in which a speed-variable driving force source isprovided for an upper roll in each stage respectively so that a drivingforce for the endless belt for each stage can freely be adjusted andchanged, an optimum rotating speed for the cereal grains suppliedthereto can be realized for each stage, and because of thisconfiguration, the roll sorting machine can treat various types ofcereal grains more flexibly.

Further when the roll sorting machine is embodied as a multiple stageroll sorting machine in which a constant rate supply unit for supplyingcereal grains to feedstock cereal grain inlet for each stage so that asupply rate of the feedstock cereal grains can freely be adjusted, it ispossible to supply the feedstock cereal grains to each stage understable and uniform conditions, which is more preferable.

Further, when a roll sorting process is carried out with the rollsorting machine in a cereal grain sorting system, the cereal grainsorting system becomes more advantageous in terms of its sortingprecision, operational stability, and safety during operations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a general explanatory view showing a flow of a cereal grainsorting system according to the present invention viewed from its side;

FIG. 2 is an explanatory view showing a sucking type of wind forcesorting machine used in the cereal grain sorting system according to thepresent invention viewed from its front side;

FIG. 3 is an explanatory view showing a rough sorting machine used inthe cereal grain sorting system according to the present invention;

FIG. 4 is an explanatory view showing a side view of a drum-shapedmagnetic sorting machine used in the cereal grain sorting systemaccording to the present invention;

FIG. 5 is an explanatory view showing a side view of a stone-piecescreening machine used in the cereal grain sorting system according tothe present invention;

FIG. 6 is an explanatory view showing a polishing machine used in thecereal grain sorting system according to the present invention;

FIG. 7 is an explanatory view showing a grain-diameter sorting machineused in the cereal grain sorting system according to the presentinvention;

FIG. 8 is a perspective view showing one embodiment of a roll sortingmachine according to the present invention;

FIG. 9 is an explanatory view showing the arrangement of a lower roll aswell as of an upper roll in the roll sorting machine according to thepresent invention viewed from the front side;

FIG. 10 is an explanatory view showing the arrangement of the lower rolland upper roll in the roll sorting machine according to the presentinvention viewed from the side thereof;

FIG. 11 is a side view showing one embodiment of a multiple stage rollsorting machine according to the present invention;

FIG. 12 is a front view showing one embodiment of the multiple stageroll sorting machine according to the present invention; and

FIG. 13 is a general side view showing a case where the multiple stageroll sorting machine according to the present invention is of an erectedtype.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the cereal grain sorting system according to the presentinvention are described below. It is to be noted that the embodimentsare described herein for illustrative purpose, and that this inventionis not limited to the embodiments.

In FIG. 1, the reference letter A indicates feedstock cereal grains asan object for processing by the cereal grain sorting system according tothe present invention, the reference letter D indicates the foreignmaterials sorted and removed in each of the steps described above, thereference letter S indicates a lift transferring the cereal grains upand down between the processing processes, the reference letter Bindicates a belt conveyor for transporting the feedstock cereal grainsA, and the reference letter Z indicates the sorted final products.

The reference numeral 100 indicates a sucking type of wind force sortingmachine for carrying out the wind force sorting process for selectivelyremoving light weight foreign materials from the cereal grains. Thissucking type of wind force sorting machine 100 selectively removes lightweight foreign materials (dust, coats, and other small refuse) with asucking wind force. Any known type of wind force sorting machine may beused for this wind force sorting machine.

The reference numeral 200 indicates a rough sorting machine for roughlysorting foreign materials having been subjected to the sorting processfor selectively removing light weight foreign materials from thefeedstock cereal grains A in the wind force sorting process describedabove and yet having diameters from a standard one respectively. Thisrough sorting machine 200 selectively removes foreign materials having alarger diameter from the standard one (such ascorn, mud blocks, andstone pieces) and those having a smaller diameter from the standard one(such as seeds, glass seeds, and small stone pieces) by means of sievingperformed by vibrating a punching plate for remaining foreign materialshaving a larger diameter from the standard one thereon and also fordropping those having a smaller diameter from the standard onetherefrom. Any known type of rough sorting machine (grain diametersorting machine) may be used for this rough sorting machine.

The rough sorting process may be carried out before the wind forcesorting process.

The reference numeral 300 indicates a drum-shaped magnetic sortingmachine for selectively removing magnetic foreign materials from thecereal grains A having been subjected to the rough sorting processdescribed above for selectively sorting foreign materials having adifferent diameter from the standard one. This drum-shaped magneticsorting machine 300 selectively removes magnetic foreign materials suchas metallic substances by making use of an attracting effect of a magnetprovided inside a rotary drum. Any known type of drum-shaped magneticsorting machine may be used for the drum-shaped magnetic sortingmachine.

The magnetic sorting process with this drum-shaped magnetic sortingmachine 300 may be provided only when magnetic foreign materials such asmetal pieces are mixed in the feedstock cereal grains A, and when it isclear that any magnetic foreign material is not mixed in the cerealgrains, the process is not necessary, and in addition this magneticsorting process may be performed between any process in the cereal grainsorting system according to the present invention.

The reference numeral 400 indicates a stone-piece removing machine usedin the stone-piece removal process for selectively removing stone piecesfrom the cereal grains A having been subjected to the magnetic sortingprocess as described above for selectively removing magnetic foreignmaterials. This stone-piece removing machine 400 selectively removesstone pieces by sending air from under a porous sorting plate inclinedto a direction and vibrating the porous sorting plate to move only heavystone pieces to the inclined upper side of the inclined screen. Anyknown type of stone-piece removing machine may be used for thestone-piece removing machine.

The stone-piece removal process with this stone-piece removing machine400 may be provided only when it is clear that stone pieces are mixed inthe feedstock cereal grains A, and this process may be eliminated whenit is clear that stone pieces are not mixed in the feedstock cerealgrains A, and further this process may be carried out between anyprocesses in the cereal grain sorting system according to the presentinvention.

The reference numerals 500 a and 500 b each indicate a polishing machineused in a polishing process for polishing off and removing fine deposits(such as dust, mud and the like) from the cereal grains A having beensubjected to the stone-piece removal process for selectively removingstone pieces. In the polishing machine 500 a, 500 b, a plurality ofpolishing belts are provided in a radial form along an internalperipheral surface of a fixed cylindrical net-formed screen, and finedeposits are polished off and removed by rotating and moving thepolishing belt along the net-formed screen and passing the feedstockcereal grains A between the net-formed screen and the polishing belt.Any known type of polishing machine may be used for this polishingmachine.

This polishing process with the polishing machine 500 a, 500 b may beprovided only when fine deposits are present on the feedstock cerealgrains A, and when it is clear that fine deposits are not on thefeedstock cereal grains A, this process may be omitted. Further thisprocess may be carried out between any processes in the cereal grainsorting system according to the present invention.

The reference numerals 600 a, 600 b each indicate a grain diametersorting machine for sorting the cereal grains A having been subjected tothe polishing process described above for polishing off and removingfine deposits on the cereal grains A according to a diameter of eachgrain (large diameter grains, medium diameter grains, and small diametergrains). The grain diameter sorting machine 600 a, 600 b sorts thefeedstock cereal grains A according to the diameters by vibrating thepunching plate for leaving foreign materials having a larger diameterfrom the standard one and dropping those having a smaller diameter fromthe standard one to under the punching plate. Any known type of graindiameter sorting machine may be used for this grain diameter sortingmachine.

The grain diameter sorting process with the grain diameter sortingmachine 600 a, 600 b may be omitted when it is not required to sort thefinal products according to their grain diameters, and may be carriedout between any two steps in the cereal grain sorting system accordingto the present invention. Preferably this grain diameter sorting processshould be carried out immediately before or after the roll sortingprocess.

The reference numerals 700 a, 700 b, 700 c each indicates a roll sortingmachine for selectively removing foreign materials having formsdifferent from that of the cereal grains A having been subjected to thegrain diameter sorting process for sorting the cereal grains A accordingto grain diameters (those having flat forms, angular forms, orirregularly round forms which can not rotate smoothly). In this rollsorting machines 700 a, 700 b, and 700 c, an endless belt is hung over alower roll and an upper roll arranged diagonally above the lower roll,the lower and upper rolls are inclined in one direction at aprespecified angle respectively with the inclination angle of the lowerroll smaller than that of the upper roll, further one or moresaw-toothed plates are provided on a top surface of the endless belt, alengthy inclined discharge plate inclining downward is provideddiagonally under the downwardly inclining side of the endless belt. Whenthe endless belt is rotated in the direction to the upper roll, therotatable round materials (acceptable products) rotates and dropdownward, while the non-rotatable foreign materials do not rotate andare carried in the direction to the upper roll, where foreign materialshaving different forms are selectively removed. Any known roll sortingmachine may be used for the roll sorting machine, but the roll sortingmachine according to the present invention is more advantageous forinstance in terms of sorting precision, operating stability, and safetyduring operation thereof.

Further in each of the machines used in each process described above,further a dust collector may be provided, and when the dust collector isadditionally provided in each of the machines described above, fine dustand other foreign materials can be removed with a quality of acceptableproducts further improved, and also the atmosphere at the working siteis further cleaned.

As described above, with the cereal grain sorting system according tothe present invention, a specific gravity sorting machine requiring alarge quantity of air to be supplied is not necessary, and stableoperations can be performed for a long time without deteriorating theatmosphere at the working site, and further it is possible to obtainhigh quality final products relatively quietly maintaining the sortingprecision and production yield.

Examples of the machines which can advantageously be used in the cerealgrain sorting system according to the present invention are describedbelow.

In FIG. 2, the reference numeral 100 indicates a sucking type of windforce sorting machine (so called gravity separator). The sucking type ofwind force sorting machine 100 is based on a double structure consistingof a cylindrical external frame body 101 and an internal frame body 102,and a ventilation section 110 through which air is sent from down to upis provided between the external frame body 101 and internal frame body102. A dust collection port 112 is provided at an upper edge section ofthe sucking type of wind force sorting machine 100, and the dust issucked by the dust collector. An inspection port 113 is provided on aside face of the external frame body 101 for convenience in maintenancework.

In the wind force sorting machine 100 described above, when feedstockcereal grains are fed from a feedstock inlet 111 provided in an uppersection of the sucking type of wind force sorting machine 100, thefeedstock passes through an feedstock inlet pipe 124 having a flow rateadjustment shutter 123 provided at its lower end, and is delivered ontoa rotary plate 122 rotated and driven by a motor M via a bevel gear 121.The delivered feedstock cereal grains are dispersed in radial directionsby the rotary plate 122, slip down along a surface of a conical section131 in an upper section of the internal cylindrical body 130 and try todrop through the ventilation section 110, but as air is blown from thebottom to top through the ventilation section 110, so that light weightforeign materials such as dust, coats, glass seeds, and small refuse aresucked upward and collected through a dust collection port 112, or arecollected in a dust receiving body 132 and discharged from a dust exit114 to the outside, while the acceptable products having a differentspecific weight drop through the ventilation section 110 as they are andare discharged from an acceptable product outlet 115. The feedstockcereal grains are divided to acceptable products and light weightforeign materials to be disposed.

In FIG. 3, the reference numeral 200 indicates a rough sorting machine.The rough sorting machine 200 is supported with a support tool 204 on abase 208, and comprises a feedstock hopper 201, a crankshaft 203, ahandle body 205 c joined to the crankshaft 203, a motor M for rotatingand driving the crankshaft 203, a large grain diameter material chute221, an intermediate grain diameter chute 222, a small grain diameterchute 223, and a fine grain diameter material chute 224. Punching plates211 for various classes of grain diameters are provided inside a casing202. When the crankshaft 203 is rotated and driven by the motor M, thecasing 202 is vibrated back and forth.

In the rough sorting machine 200, when feedstock cereal grains are fedfrom the feedstock hopper 201 and is transferred onto the punchingplates 211 inside the casing 202, the feedstock cereal grains are sieveddue to vibration and also to roughness of meshes of the punching plateaccording to the grain diameters, and foreign materials having a largediameter such as corn, stems, and large stone pieces are discharged fromthe large grain diameter material chute 221, foreign materials having asmall diameter such as cracked beans, glass seeds, and small stonepieces are discharged from the small grain diameter chute 223, foreignmaterials having a fine diameter such as dust or the like are dischargedfrom the fine grain diameter chute 224, and acceptable products aredischarged from the medium grain diameter chute 222. Thus the feedstockcereal grains are separated to acceptable products and foreign materialshaving different diameters from the standard diameter of the acceptableproducts.

In FIG. 4, the reference numeral 300 indicates a drum-shaped magneticsorting machine. The drum-shaped magnetic sorting machine 300 comprisesa feedstock hopper 301, a dust collection pipe 302, and a motor M with adrum 310 and a partition member 311 provided inside a casing 302, andthe a non-magnetic material outlet 312 is separated by the partitionmember 311 from a magnetic material output 313.

In the drum-shaped magnetic sorting machine 300, when the feedstockcereal grains are fed from the feedstock hopper 301 and are suppliedonto the drum rotated and driven by the motor M, magnetic foreignmaterials such as metal pieces are attracted to a surface of the drum310 because of the effects of a semi-circular magnet 320 provided insidethe drum 310, transported to a lower edge of the semi-circular magnetand are discharged from a magnetic material outlet 313, while, as theacceptable products are non-magnetic, they are not attracted to asurface of the drum 310, drop as they are, and are discharged from thenon-magnetic outlet 312. Thus the feedstock cereal grains are divided toacceptable products and magnetic foreign materials.

In FIG. 5, the reference numeral 400 indicates a stone-piece removingmachine. The stone-piece removing machine 400 has a porous sorting plate408 accommodated in a vibration box 414, and as shown in the figure, theporous sorting plate 408 is inclined at an appropriate angle. Thisinclination angle may be adjusted according to the necessity. Thereference numeral 432 indicates a hood, and a feedstock hopper 422 isprovided in the hood 432. The reference numeral 405 indicates an airchannel provided in a lower section of the vibration box 414, and ablower fan unit 406 is accommodated in the air channel 405. It should benoted that the reference numeral 410 indicates a motor for driving thefan unit 406 and the reference numeral 434 indicates a dust outlet portcommunication to the fan unit 406.

The reference numeral 418 is an eccentric crank, which is driven by themotor 420. The eccentric crank 418 is connected to a lever 416 joined tothe vibration box 414. When a rotating movement of the eccentric crank418 is delivered as a reciprocal movement to the vibration box 414, thevibration box 414 and the porous sorting plate 408 provided in thevibration box 414 vibrate (oscillate) around an upper section of thearm.

The reference numeral 424 indicates a discharge port formed at an upperedge section of the porous sorting plate 408 for stone pieces with alarge specific weight, while the reference numeral 426 indicates adischarge port formed at a lower edge of the porous sorting plate 58 foracceptable products with a relatively small specific weight.

In the stone-piece removing machine 400, the feedstock cereal grains aresupplied to a central portion of the porous sorting plate 408, and airis blown upward from under the porous sorting plate 408 to flow thefeedstock cereal grains. Because of this flow, acceptable products witha smaller specific weight than that of stone pieces come to the upperside from the stone pieces having a larger specific weight. The heaviermaterials in the lower side move diagonally upward in association withvibration of the porous sorting plate 408. The acceptable products inthe upper side are little affected by the vibration effect, and movediagonally downward as the porous sorting plate 408 is inclined. The airis discharged from the dust collector pipe 428. As described above, thefeedstock cereal grains are separated to acceptable products and stonepieces.

In FIG. 6, the reference numeral 500 indicates a polishing machine. Thepolishing machine 500 has a parallel polishing belt 518 and an inclinedpolishing belt 519 alternately provided along an internal peripheralsurface of the cylindrical net-formed screen (not shown) in the radialform, and when the rotating shaft 510 is rotated, the parallel polishingbelt 518 and inclined polishing belt 519 rotate along the internalperipheral surface of the cylindrical net-formed screen. The rotatingshaft 510 is rotated by a belt hung over a rotating disk 512 which isrotated and driven by the motor M and a rotating disk 511 for rotatingthe rotating shaft 510. In this figure, further designated at thereference numeral 504 is a dust collection port, at 505 a dust collectorpipe, at 506 a dust outlet, and at 501 a base.

In the polishing machine 500, when the feedstock cereal grains are fedfrom the feedstock hopper 502 and is supplied to the cylindricalnet-formed screen, the feedstock cereal grains are polished by theparallel polishing belt 518 and inclined polishing belt 519 rotated anddriven by the motor M with fine deposits removed therefrom, and thefeedstock cereal grains are transferred by the feed effect by theinclined polishing belt 519 and are discharged from the acceptableproduct outlet 508. Thus the feedstock cereal grains are separated toacceptable products and fine deposits.

In FIG. 7, the reference numeral 600 indicates a grain diameter sortingmachine. The grain diameter sorting machine 600 is a two-stage unit. Inthis figure, designated at the reference numeral 608 is a feedstockhopper, at 604 a hunger, at 606 a crankshaft, and at M a motor. Furtherin this figure, designated at the reference numeral 610 is a large graindiameter material collection chute, at 612 a medium diameter materialcollection chute, at 614 a small grain diameter material collectionchute, and at 616 a fine grain diameter material collection chute.Punching plates 622 for various grain diameter classes are providedinside the casing 602. The casing 602 is mounted via a hunger 604 to aframe 603, and when the crankshaft 606 is rotated by the motor M, thecasing 602 is vibrated back and forth.

In the grain diameter sorting machine 600, when the feedstock cerealgrains are fed from the feedstock hopper 608 and are supplied onto thepunching plates 622 inside the casing 602, the feedstock cereal grainsare sieved according to the grain size classes because of vibration anddue to differences in mesh roughness of the punching plates 622, and thelarge grain diameter materials are discharged from the large graindiameter material collection chute 610, the medium grain diametermaterials are discharged from the medium grain diameter materialcollection chute 612, the small grain diameter materials are dischargedfrom the small grain diameter material collection chute 614, and thefine grain diameter materials are discharged from the fine graindiameter material collection chute 616. The fine grain diametermaterials are treated not as acceptable products, but as fine foreignmaterials. Thus the feedstock cereal grains are separated to large graindiameter materials, medium grain diameter materials, small graindiameter materials, and fine grain diameter materials.

An embodiment of the roll sorting machine according to the presentinvention which can be incorporated in the feedstock cereal grainsorting system according to the present invention is described below,but it is to be noted that the embodiment is provided for theillustrative purpose and that this invention is not limited to thisembodiment. For convenience in descriptions, description of theembodiment assumes a case where feedstock soybeans with foreignmaterials and defective products mixed therein are sorted.

FIG. 8 is a perspective view showing one embodiment of the roll sortingmachine according to the present invention, and in this figure thereference numeral 1 indicates the roll sorting machine according to thepresent invention. The roll sorting machine 1 has an endless belt 4 hungover a lower roll 2 and an upper roll 3 provided diagonally above thelower roll 2.

The lower roll 2 and upper roll 3 are provided with the same edgesections (right-hand edge sections in FIG. 9) downwardly inclining atprespecified angles of α and β respectively as shown in FIG. 9. As forthe inclination angles of α and β of lower and upper rolls, theinclination angle α should preferably be smaller than the inclination βto insure the good sorting effect. The inclination α should preferablybe in the range from 0.5 to 3.0 degrees, while the inclination β shouldpreferably be in the range from 5.0 to 9.0 degrees.

Also as shown in FIG. 10, the upper roll 3 should be located diagonallyabove the lower roll 2 at a prespecified angle of γ. As for the anglebetween a central axis of the upper roll 3 and a central shaft of thelower roll 2, the angle γ between lower edges of the respective centralshafts should preferably be in the range from 3.0 to 6.0 degrees, andthe angle δ between the upper edges thereof should preferably be in therange from 5.0 to 9.0 degrees.

Therefore, as the inclination a is smaller than the inclination angle β,the endless belt 4 is hung over the lower roll 2 and upper roll 3 in thediagonally upward twisted state.

It is needless to say that, when the inclination angles α and β and theinclination angles γ and δ are larger or smaller than the respectivespecified angles, sorting can not be performed in good conditions, butas the inclination angles should change according to a feedstock to besorted, each of the inclination angles should be decided according totypes of feedstocks to be sorted.

The upper roll 3 is a drive roll with a direct connection type ofspeed-variable driving force source 20 directly connected to one edgethereof. The driving speed for the endless belt is adjusted to anoptimum value according to a form of a feedstock to be sorted so thatthe feedstock rotates and drops most efficiently with the directconnection type of speed-variable driving force source 20.

In the case of a feedstock having an oval form such as soybeans, as thefeedstock hardly start rotation, the driving speed should be raised to asufficient speed before the feedstock starts rotation. In the case of afeedstock having a spheric form such as a pearl, as the feedstock easilystarts rotation at a low speed, so that the driving speed should be setto a low value.

Check of the rotating state of a feedstock may visually be performed,and when monitoring is performed in a monitor camera 30 in a remotemode, the work load is reduced, which results in reduction of laborcost. Namely whether the feedstock fed onto a top surface of the endlessbelt is rotating appropriately is monitored with the monitor camera 30in the remote mode, and a driving speed for the endless belt is adjustedto an optimum value according to a form of the feedstock to be sorted byadjusting the direct connection type of speed-variable driving forcesource 20. Similarly, the inclination angles α, β of the upper roll 3and lower roll 2 and the angles γ, δ between the central shaft of theupper roll 3 and that of the lower roll 2 should be adjusted to theoptimum values respectively according to a form of a feedstock to besorted.

When the upper roll 3 is driven, the endless belt 4 rotate in thedirection indicated by arrow X, and a top surface thereof is moved inthe direction to the upper roll 3.

The reference numeral 6 indicates a bean receiving bar provided on a topsurface of the endless belt 4, and is provided so that it forms asubstantially L-shaped form at a belt edge section of the endless beltin the not-inclining side (the left-hand edge section in FIG. 8) and abelt surface in the lower roll side 2.

The reference 7 indicates a table provided under an upper surface of theendless belt 4 for preventing the endless belt 4 from becoming loose,and an inclined discharge plate 7 a inclining downwardly and functioningas a outlet for discharging sorted soybeans are provided in the sideedge section of the endless belt 4 in the downwardly inclining sidethereof.

The reference numerals 8 a, 8 b, and 8 c indicate saw-toothed plateseach having a saw-toothed form in the lower side and arranged at anappropriate space therebetween in the horizontal direction on a topsurface of the endless belt 4. There is no specific restriction over amaterial for the saw-toothed plates 8 a, 8 b, and 8 c, but rubber shouldpreferably be used. The saw-toothed plates 8 a, 8 b, 8 c break forsorting a pile of soybeans as a feedstock fed onto a top surface of theendless belt 4 from the feedstock soybean inlet A so that the sortingoperation performed on a top surface of the endless belt 4 canefficiently be performed.

Supply of feedstock soybeans is performed by a constant rate supply unit22 to a supply point P₁ surrounded by the bean receiving bar 6 and thesaw-toothed plate 8 a on a top surface of the endless belt 4. Any typeof constant rate supply unit may be used for the constant rate supplyunit 22 so long as it has a constant rate supply mechanism for supplyinga feedstock at a constant rate, and a supply rate of a feedstock shouldbe adjusted so that the feedstock will not overflow from nor causeclogging at the supply point P₁. The constant rate supply unit 22 may beone having a vibration mechanism, and in this case, the fed feedstock isscattered due to vibration and does not form a pile at the feedstocksoybean inlet A, so that, of the saw-toothed plates 8 a, 8 b, and 8 c,the saw-toothed plate 8 a may be omitted.

The reference numerals 9 a and 9 b each indicate a take-up provided atboth edge sections of the lower roll 2 for adjusting tension of theendless belt 4.

The reference numeral 10 a indicates a bean leakage prevention roll andis provided diagonally under the upper roll 3 at a position closethereto, namely so that it contacts an upper side section of the rightside endless belt 4 in FIG. 8, and functions to prevent leakage of beansto be sorted. On the other hand, the reference numeral 10 b is a snakingprevention roll, and is provided diagonally above the lower roll 2 at aposition close thereto, namely so that it contacts a lower side edgesection of the left side endless belt 4 in FIG. 8, and functions toprevent the belt from snaking.

The reference numerals 11 a, 11 b indicates guide plates for adjustingflow of soybeans provided at both edge sections of the inclineddischarge section 7 a of the table 7.

The reference numeral 13 is a sorted product outlet provided outside theinclined discharge plate, which is separated by a partition section 16to an outlet 13 a for acceptable products (soybeans and red beans havingthe regular forms, or spherical materials such as pearls) and an outlet13 b for secondary products including rotatable defective products (suchas cracked beans having forms similar to but different from a sphericalform, worm-eaten beans).

With the configuration described above, now the effects are describedbelow. At first, when the upper roll 3 is driven, a top surface of theendless belt 4 moves toward the upper roll 3. When feedstock soybeansincluding foreign materials such as stone pieces, stems, and worm-eatenbeans or defective products are fed from the feedstock inlet A to thesupply point P₁ on a top surface of the endless belt 4, the feedstocksoybeans move in the direction to the upper roll 3 in association withmovement of the endless belt 4 and at the same time soybeans having theregular form immediately start rotating and dropping diagonally underthe belt 4 and are discharged from the acceptable product outlet 13 avia the inclined discharge section 7 a and are accommodated in a beanreceiving vessel not shown in the figure.

The soybeans piled up at the supply point P₁ contact and collide withthe first saw-toothed plate 8 a with the pile of soybeans broken andsorted. Soybeans having the regular form falling down from the brokenpile similarly start rotation and are discharged from the acceptableproduct outlet 13 a into a bean receiving vessel (not shown). Then, whenthe soybeans reach the supply point P₂, the soybeans having the regularform rotate and move diagonally downward under the endless belt 4,namely in the direction to a right edge section of the belt 4 in FIG. 1,pass through the inclined discharge section 7 a of the table 7, and aredischarged from the acceptable product outlet 13 a or the second outlet13 b and are accommodated in the respective bean receiving vessels.

In this step, foreign materials other than the soybeans having theregular form such as flat or angular stone pieces, mud blocks, and stemswhich can not rotate smoothly move without rotating in the direction tothe upper roll 3 in association with movement of the belt 4. Then at thepoint P₃, the soybeans pass over the second saw-toothed plate 8 b to beseparated further each other, and the soybeans having been released fromthe piled-up state rotate and move downward, and are discharged from theacceptable product outlet 13 a or the second outlet 13 b and areaccommodated in the respective bean receiving vessels.

Foreign materials not rotatable do not move themselves nor drop, andmove in association with movement of the endless belt 4. At the pointsP₁, P₂, and P₃, most of the soybeans having the regular form rotate anddrop and are discharged from the acceptable outlet 13 a or from thesecond outlet 13 b. A very small quantity of soybeans having the regularbeans not having rotated, for instance, because they lodge on foreignmaterials or the like also start rotating when they contact the thirdsaw-toothed plate 8 c and are sorted thereby, and are discharged fromthe second outlet 13 b.

Of the foreign materials other than the soybeans having the regularform, those such as angular materials and stems, which do not rotate atall, move in association with movement of the belt 4 and reach the pointP₄, where the foreign materials are discharged from a foreign materialoutlet C and drop into a foreign material receiving vessel (not shown).On the other hand, defective products such as flat form materials,cracked beans, and worm-eaten beans which rotate slightly reach thepoint P₃ or point P₄ according to a degree of their rotation. All of therotatable but defective products having reached the point P₄ rotatedownward and are discharged from the second outlet 13 b. Most of therotatable but defective products having reached the point P₃ aredischarged from the second outlet 13 b.

A twist angle of a top surface of the endless belt 4 becomes abruptlylarge as it goes higher, so that a rotating state of beans varies fromplace to place on a top surface of the endless belt 4, and this finechange in a twist angle of this endless belt 4 makes it possible toaccurately differentiate normal beans (acceptable products) fromdefective beans (non-rotatable defective products). Further as comparedto a case where a top surface of the endless belt 4 is not twisted butis simply flat, the distance required for sorting may be shorter, whichenables compact structure.

The feedstock soybeans fed to the supply point P₁ are never moved norscattered by the bean receiving bar 6 in the direction to the lower roll2 or upward along inclination of the belt 4. Further when centralportions of the saw-toothed plates 8 a, 8 b, and 8 c are flexible asshown in FIG. 8, a clearance from a surface of the belt 4 can freely beadjusted, so that treating and sorting the feedstock soybeans piled upcan freely be adjusted according to the feeding situation of thefeedstock soybeans. A number of the saw-toothed plates 8 a, 8 b, and 8 cis not limited to that in the embodiment described above, and anydesired number of the saw-toothed plates may be installed.

It is preferable to use rubber-coated cloth for the endless belt 4, andby making smooth a surface of the belt, it becomes easier to catchforeign materials and defective grains. On the contrary, when theconventional canvas cloth for the belt, it is not easy to catch foreignmaterials, and further it is disadvantageously impossible to preventsnaking of the canvas cloth.

As described above, in the roll sorting machine according to the presentinvention, clogging at the feedstock cereal grain inlet or lowering ofthe sorting precision never occurs even when cereal grains more than thenormal processing capacity of the machine are supplied. Further, themachine never contaminates the feedstock cereal grains, can ensuresafety for workers, and can prevent the sorting precision from varyingdue to a difference of forms of cereal grains.

Although description of the embodiment above assumed a case where anglesof the upper roll 3 and lower roll 2 are set so that the entire rollsorting machine is kept in the horizontal posture, the entire rollsorting machine 1 can be installed at a specified angle by using araising means such as a jack machine.

Further description of the embodiment above assumed a case where onlyone unit of roll sorting machine 1 is provided, but for actually sortinga vast quantity of feedstock soybeans, it is necessary to provide amultiple unit of roll sorting machines 1 for insuring a higherthroughput. The examples are shown in FIG. 11 and FIG. 12. FIG. 11 is aside view showing a multi-stage type of roll sorting machine 1A, whileFIG. 12 is a front view showing the multi-stage type of roll sortingmachine 1A. In the examples, 12 units of roll sorting machines 1 arelaid on each other in the vertical direction. In the figure, designatedat the reference numeral 11 is a feedstock hopper, at 12 a feedstocksoybean chute, and at 13 a sorted material outlet.

In the figure, the reference numerals 20 a to 20 l indicates directconnection type of speed-variable driving force sources each directlyconnected to an edge of an upper roll in each stage, and with the directconnection type of speed-variable driving force sources, a speed of theendless belt in each stage can be adjusted independently. With thisconfiguration, a rotating speed of the endless belt in each stage canfreely be adjusted to an optimum value according to a form of feedstocksupplied thereto, which in turn makes it possible to treat various typesof feedstocks more flexibly. Further as a chain is not required, thetroubles and contamination caused by a chain as described above can beeliminated.

Further in this figure, designated at the reference numeral 18 is avibration type of constant rate supply unit, and at 16 a urethane rubberpipe. In the case of multiple stage system, it is possible to supplyfeedstock with one vibration type of constant rate supply unit throughthe pipe 16 at a constant rate.

In the multiple stage roll sorting machine described above, the rollsorting machine 1 on each stage is diagonally displaced from theadjoining lower one, but an elected posture type of multiple stagesorting machine in which all of the roll sorting machines may be stackedin the vertical direction is allowable, and in this case, an arearequired for installation may be small, which is advantageous for spacesaving. For instance, in the case of the 12-stage inclined type of rollsorting machine, the area required for installation thereof is about 1.8m (width)×5 m (length)×4.5 m (height), but in the case of the 12-stageerected type of roll sorting machine, the area required for installationthereof is only about 1.8 m(width)×2.7 m (length)×4.5 m (height), and asthe area required for installation of the 12-stage erected type of rollsorting machine is only about a half of that for the 12-stage inclinedtype of roll sorting machine, which allows effective use of even anarrow area for installation. The example is shown in FIG. 13.

In this figure, designated at the reference numeral 11 is a feedstockhopper, at 13 a sorted material outlet, at 18 a vibration type ofconstant rate supply unit, at 20 a to 20 l each a direct connection typeof speed-variable driving force source.

Description of the embodiment of the roll sorting machine according tothe present invention above assumed a case of sorting soybeans, but thepresent invention is not limited to this embodiment. The roll sortingmachine according to the present invention can sort not only sphericalmaterials such as red beans and pearls, but also any materials which canrotate and have a form similar to a sphere, and therefore the rollsorting machine according to the present invention can widely be usedfor sorting cereal grains.

Capability of Exploitation in Industry

As described above, with the present invention, it has become possibleto provide a cereal grain sorting system which eliminates the necessityof a specific gravity sorting machine requiring supply of a vastquantity of air and insures quiet, stable and long-term operationswithout deteriorating the labor environment and with high sortingprecision as well as high production yield, and also which makes itpossible to obtain high quality final products.

Further it has become possible to provide a roll sorting machine inwhich clogging at the feedstock cereal grain inlet or lowering of thesorting precision never occurs even when cereal grains more than thenormal processing capacity of the machine are supplied. It also hasbecome possible to provide the machine which never contaminates thefeedstock cereal, to ensure safety for workers, and to prevent thesorting precision from varying due to a difference of forms of cerealgrains.

What is claimed is:
 1. A cereal grain sorting system comprising: a windforce sorting device operative for selectively sorting light weightforeign materials from feedstock cereal grains; a rough sorting deviceoperative for selectively removing foreign materials having differentdiameters from the standard one from the feedstock cereal grains; and aroll sorting device operative for selectively removing foreign materialshaving different forms from the standard ones from the feedstock cerealgrains having been subjected to said wind force sorting step as well asto said rough sorting step, the roll sorting device including at leastone endless belt unit having an endless belt wrapped about an upper rolland a lower roll disposed apart from and below the upper roll as viewedin elevation such that an upper surface of the endless belt inclinesupwardly from the lower roll to the upper roll as viewed in a beltmoving direction and inclines transversely relative to the belt movingdirection and downwardly from a feedstock supply side of the endlessbelt to a feedstock discharge side of the endless belt wherein the upperroll inclines downwardly relative to the feedstock supply side at afirst downwardly inclination angle and the lower roll inclinesdownwardly relative to the feedstock supply side at a second downwardlyinclination angle thereby resulting in a twisted endless belt surfacetwisting from the lower roll at the feedstock supply side to the upperroll toward the feedstock discharge side while the upper surface of theendless belt inclines upwardly and moves from the lower roll to theupper roll.
 2. The cereal grain sorting system according to claim 1further comprising: a magnetic force sorting device operative forselectively removing magnetic foreign materials from the feedstockcereal grains.
 3. The cereal grain sorting system according to claim 1further comprising: a stone piece removal device operative forselectively removing stone pieces from the feedstock cereal grains. 4.The cereal grain sorting system according to claim 1 further comprising:a polishing device operative for polishing off and removing finedeposits from the feedstock cereal grains.
 5. The cereal grain sortingsystem according to claim 1 further comprising: a grain diameter sortingdevice operative for selectively removing feedstock cereal grainsaccording to the grain diameters.
 6. A cereal grain sorting systemcomprising: wind force sorting means for selectively sorting lightweight foreign materials from feedstock cereal grains; rough sortingmeans for selectively removing foreign materials having differentdiameters from the standard one from the feedstock cereal grains; androll sorting means for selectively removing foreign materials havingdifferent forms from the standard ones from the feedstock cereal grainshaving been subjected to said wind force sorting means as well as tosaid rough sorting means, the roll sorting means including at least oneendless belt unit having an endless belt wrapped about an upper roll anda lower roll disposed apart from and below the upper roll as viewed inelevation such that an upper surface of the endless belt inclinesupwardly from the lower roll to the upper roll as viewed in a beltmoving direction and inclines transversely relative to the belt movingdirection and downwardly from a feedstock supply side of the endlessbelt to a feedstock discharge side of the endless belt wherein the upperroll inclines downwardly relative to the feedstock supply side at afirst downwardly inclination angle and the lower roll inclinesdownwardly relative to the feedstock supply side at a second downwardlyinclination angle thereby resulting in a twisted endless belt surfacetwisting from the lower roll at the feedstock supply side to the upperroll toward the feedstock discharge side while the upper surface of theendless belt inclines upwardly and moves from the lower roll to theupper roll.
 7. The cereal grain sorting system according to claim 6further comprising: magnetic force sorting means for selectivelyremoving magnetic foreign materials from the feedstock cereal grains. 8.The cereal grain sorting system according to claim 6 further comprising:stone piece removal means for selectively removing stone pieces from thefeedstock cereal grains.
 9. The cereal grain sorting system according toclaim 6 further comprising: polishing means for polishing off andremoving fine deposits from the feedstock cereal grains.
 10. The cerealgrain sorting system according to claim 6 further comprising: graindiameter sorting means for selectively removing feedstock cereal grainsaccording to the grain diameters.